Question

<!--td {border: 1px solid #cccccc;}br {mso-data-placement:same-cell;}--> Describe the process for the production of Lime-soda glass. [3 Mark]

Answer 1

<!--td {border: 1px solid #cccccc;}br {mso-data-placement:same-cell;}--> For glass production, mixture of sand, soda, lime, and small quantity of magnesium oxide is heated in furnace. Sand i.e. silicon dioxide melts at 1700 0 C. [1 Mark] So as to melt the mixture at low temperature, pieces of discarded glass are added to it. Due to this, mixture melts at 850 ºC. Once all the ingredients of mixture are liquified, it is heated up to 1500 ºC and immediately cooled. [1 Mark] Due to sudden cooling, mixture becomes homogenous, amorphous and transparent instead of crystalline. This is called Soda-lime glass. [1 Mark]